Wiring honeywell 2 port valve, but different.

[mightyworthit]

Not sure if this should be posted in electricians forum so apologies in advance.

I am a qualified plumber.
This is in my own house and will be implemented by a qualified electrician under my instruction.

I have a thermal store designed and installed by myself.

Off of the thermal store I have a radiator circuit, flow and return,which takes heated water from the store independent from any control of the boiler and other heat sources.

Demand for this circuit comes from a thermostat that simply switches on a pump on the flow side of the radiator circuit

I have an issue with gravity heat leak on this circuit, i.e. when there is no demand from the radiator circuit thermostat hot water will still circulate around the circuit due to gravity, effectively leaking heat from the thermal store and unnecessarily heating rads etc.

My solution is to put a 2 port valve between the thermal store and the pump that opens when the pump is switched on by the thermostat.

Effectively in series with the pump, simply connecting the live neutral and earth to switch the valve open.

However my honeywell 2 port valve has 5 wires and all the wiring diagrams ive seen instruct me for y plan or s plan etc, when I just simply need it to open when current detected and closed when not.

Is this possible?

many thanks.

 

[EFLImpudence]

It's possible but

it would be preferable to wire the valve so that it switches on the pump when it is open

as it does conventionally and switches on the boiler.

 

[winston1]

I'm not a plumber but I seem to remember fitting a simple non return valve in a heating flow circuit many years ago to solve a similar problem. The valve effectively remain closed until the pressure of the pump opened it.

 

[eveares]

The two port valves wire cores will be most likely be configured in the following way. The micro switch is typically active when the valve is open.

Brown: Live for the motor that opens the valve
Blue: Neutral for the motor that opens the valve
Orange: Micro Switch out
Grey: Micro Switch in
Yellow/Green: Protective Earth


If you want the micro switch to activate the pump, then wire the thermostat in series with the valve's motor and then the pump in series with the valves micro switch with the grey wire being wired to a permanent live and the orange wire to the pump's live terminal. If you don't want to use the valve's micro switch, the just wire the valves motor in parallel with the existing pump.

The micro switch has the advantage that if the thermostat breaks or the valves motor breaks, you can still use the pump by manually opening the valve. The disadvantage is if the micro switch breaks, you could end up with the pump permanently on or off regardless of the valves position depending in which state the micro switch breaks in.

Regards: Elliott.

 

[Lectrician]

I agree. Stat opens valve, valve fires pump. This is the way it should have been from the start

 

[slippyr4]

This was cross posted to the plumbing forum and has been answered there

 

[Lectrician]

The two port valves wire cores will be most likely be configured in the following way. The micro switch is typically active when the valve is open.

Brown: Live for the motor that opens the valve
Blue: Neutral for the motor that opens the valve
Orange: Micro Switch out
Grey: Micro Switch in
Yellow/Green: Protective Earth


If you want the micro switch to activate the pump, then wire the thermostat in series with the valve's motor and then the pump in series with the valves micro switch with the grey wire being wired to a permanent live and the orange wire to the pump's live terminal. If you don't want to use the valve's micro switch, the just wire the valves motor in parallel with the existing pump.

The micro switch has the advantage that if the thermostat breaks or the valves motor breaks, you can still use the pump by manually opening the valve. The disadvantage is if the micro switch breaks, you could end up with the pump permanently on or off regardless of the valves position depending in which state the micro switch breaks in.

Regards: Elliott.

Manually opening the valve on the lever (intended for filling, flushing and bleeding) does not operate the micro switch.

 

[Echo the husky]

It does on some of the newer Honeywell ones!